Question 1 - After the 5 or so days 5 of them are displaying the usual behaviour of dancing in the powerhead and filter flows whilst lights are out and foraging the substrate when lights are on. The last one is quite lethargic although he/she is still eating. This one is smaller than the others (3cm compared to 4cm) and tends to have long rest periods inbetween a bit of foraging and it will stay on the substrate (in the open, not hiding.) Only moves in these 'rest' periods when disturbed by another inhabitant. I was wondering if maybe one isnt doing so well.
Question 2 - I would quite like them to spawn but am not intending to remove eggs into containers etc. Can I expect any survivors from the eggs if I leave them in situ within the tank? The only foods I have are frozen bloodworm, tetra flakes, tetra pellets, first bites and catfish algae pellets. I have previously had livebearer fry surviving (who hasn't lol) and several spawns from Rams where the female ended up eating the fry as soon as they got too much for her (5 days or so old and free swimming).
Question 3 - There are a lot of contradicting statements on the net r.e. temperatures for Corys. I have read that for mine 23-24C is best. With this in mind I am gradually turning the heating down from the 26C that it was. The 26C was more for the other inhabitants in the tank which are cherry shrimp and microrasbora erythromicron. will this reduction be OK for them?
Question 4 - I usually use Waterlife Sterazin and run the 15 day course when I introduce new fish but haven't with these as the label has some confusing info r.e. some catfish etc. Can I use it or should I just leave it.
Any other info you think may be useful would help.
Details of my tank:
1. Water parameters
a) Temperature range - Am resetting to 24C at the moment from previous 26C
b) pH. 6.4 - 7.2 (CO2 injection do normally between 6.4 and 6.6)
c) GH. ????
d) KH ????
e)Ammonia, Nitrate, Nitrite, leavels. ????
f) Water change frequency - 10% weekly
No idea on the other tests because I tend to watch fish reactions and plants rather than testing.
2. Tank set up
a) Size - 125ltr
b) Substrate - From the bottom to the top - Mulm, Leonardite, Tropica Plant Substrate, fine play sand.
c) Filtration - Tetratec EX700 filter. There is also a powerhead rated at 400lph. These 2 give a combined lph of just under 10x tank volume. 1100lph for 125ltr tank
d) Furnishings - Heavily planted (80%) with a foreground of plain sand. Hardscape is redmoor wood.
e) Other tank mates - cherry shrimp and microrasbora erythromicron
f) How long has it been set-up? Since October 2006
Here are a few pics of them (very hard to get decent focused images of the group at the mo as they are on the move so much therefore these are mainly individual pics)




This is a pic of their new home:

Andy